package ai.zixing.mashibing.basic_class.class11;

/**
 * 打印n层汉诺塔从最左边移动到最右边的全部过程
 */
public class Code01_Hanoi {

    public static void hanoi1(int n) {
        leftToRight(n);
    }

    // 把 1~N 层圆盘：从左 -> 右
    public static void leftToRight(int n) {
        if (n == 1) {
            System.out.println("Move 1 from left to right");
            return;
        }
        leftToMid(n - 1);
        System.out.println("Move " + n + " from left fo right");
        midToRight(n - 1);
    }

    // 把 1~N 层圆盘：从左 -> 中
    public static void leftToMid(int n) {
        if (n == 1) {
            System.out.println("Move 1 from left to mid");
            return;
        }
        leftToRight(n - 1);
        System.out.println("Move " + n + " from left to mid");
        rightToMid(n - 1);
    }

    // 把 1~N 层圆盘：从右 -> 中
    public static void rightToMid(int n) {
        if (n == 1) {
            System.out.println("Move 1 from right to mid");
            return;
        }
        midToLeft(n - 1);
        System.out.println("Move " + n + " from right to mid");
        leftToRight(n - 1);
    }

    // 把 1~N 层圆盘：从中 -> 左
    public static void midToLeft(int n) {
        if (n == 1) {
            System.out.println("Move 1 from mid to left");
            return;
        }
        midToRight(n - 1);
        System.out.println("Move " + n + " from mid to left");
        rightToLeft(n - 1);
    }

    // 把 1~N 层圆盘：从中 -> 右
    public static void midToRight(int n) {
        if (n == 1) {
            System.out.println("Move 1 from mid to right");
            return;
        }
        midToLeft(n - 1);
        System.out.println("Move " + n + " from mid to right");
        leftToRight(n - 1);
    }

    // 把 1~N 层圆盘：从右 -> 左
    public static void rightToLeft(int n) {
        if (n == 1) {
            System.out.println("Move 1 from right to left");
            return;
        }
        rightToMid(n - 1);
        System.out.println("Move " + n + " from right to left");
        midToLeft(n - 1);
    }

    public static void hanoi2(int n) {
        if (n > 0) {
            func(n, "left", "right", "mid");
        }
    }

    // 1 ~ N 圆盘，目标是 from -> to, other 是另外一个
    public static void func(int N, String from, String to, String other) {
        if (N == 1) {
            System.out.println("Move 1 from " + from + " to " + to);
        } else {
            func(N - 1, from, other, to);
            System.out.println("Move " + N + " from " + from + " to " + to);
            func(N - 1, other, to, from);
        }
    }
    public static void main(String[] args) {
        int n = 3;
        hanoi1(n);
        System.out.println("================");
        hanoi2(n);
    }
}
